Foul detecting system for a bowling game

ABSTRACT

An improved bowling foul detecting system including twin retroreflective photoelectric detection systems integrated within a single housing and activated by a single light source, visual and audio alarms, and a control circuit including an 80 ms timer to distinguish ball passage, related timer circuits utilizing electronic flip-flops and programmed unijunction transistors, and incorporating SCR and triac power switching elements to control the alarms.

United States Patent [191 Crimmins et al.

FOUL DETECTING SYSTEM FOR A BOWLING GAME Inventors: William M. Crimmins; Patrick J.

Murphy; Ivan Zachev, all of Muskegon, Mich.

Assignee: The Brunswick Corporation, Skokie,

Ill.

Filed: Sept. 20, 1971 Appl. No.: 181,761

US. Cl. 273/50, 250/221 Int. Cl A63d 5/04 Field of Search 273/50, 54 E;

References Cited UNlTED STATES PATENTS 5/1936 Miller et al. 250/221 X 12/1971 Sandberg 250/221 [451 July 3, 1973 3,307,848 3/1967 Brackett et all 273/54 E 3,l70,689 2/1965 Brown et a]. 273/50 3,369,810 2/1968 Day 273/50 FOREIGN PATENTS OR APPLICATIONS 952,296 3/1964 Great Britain 273/50 Primary Examiner--A nton O. Oechsle Attor'ney- Donald S. Olexa, Sheldon L. Epstein et al.

[ 5 7 ABSTRACT An improved bowling foul detecting system, including twin retro-reflective photoelectric detection systems integrated within a single housing and activated by a single light source, visual and audio alarms, and a con trol circuit including an 80 ms timer to distinguish ball passage, related timer circuits utilizing electronic flipflops and programmed unijunction transistors, and incorporating SCR and triac power switching elements to control the alarms.

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m6 mmw mh Fr-210m FOUL DETECTING SYSTEM FOR A BOWLING GAME BACKGROUND The invention is in the field of foul detecting devices utilized in the game of bowling, and specifically relates to an improved photoelectric system for detecting and indicating the advance of a bowlers foot across the foul line of a bowling lane. Foul detectors of the type herein described are permitted by the American Bowling Congress (ABC) in lieu of a judge stationed at the foulline, and are virtually universally utilized in bowling establishments certified by the ABC.

An earlier foul detecting system described in U. S. Pat. No. 3,083,966, issued Apr. 2, 1963 to M. E. Untiedt employed a photocell at one end of the foul line actuated by a light source in a separate housing located across the lane at the other end of the foul line. When light passage was interrupted by the bowlers foot an alarm sounded. Although such an arrangement was widely used, it presented certain difficulties in that it required that electrcial components be installed on each side of each bowling lane, that both the photocell and the light source housings be carefully aligned upon installation, and that alignment of both with respect to the foul line be maintained by periodic adjustment. While modifications in the control circuitry such as those set forth in U. S. Pat. No. 3,170,689 to R. E. Brown et a1. improved upon the Untiedt device, the aforementioned problems remained.

It is a primary objective of the invention to overcome the above difficulties by providing a foul detection system which eliminates the need for a light source remote from its photodetection elements, and which is more easily installed and aligned and requires little or no alignment maintenance.

A further objective of the invention is to provide a foul detector for two adjacent lanes which may be installed in a single housing in the lane divider between the lanes.

Another objective of the invention is to provide in a single housing twin foul detection systems for two adjacent lanes, which systems employ a common light source.

A still further objective of the invention is to provide a retro-reflective foul detection system in which all active elements for an adjacent pair of bowling lanes are housed as a single unit.

It is yet another objective of the invention to provide an improved control circuit for the detection system including timer circuits utilizing programmed unijunction transistors and electronic flip-flops to control SCR and triac switching elements.

It is a still further objective of the invention to provide a control circuit incorporating a separate timer to allow for passage of a bowling ball without actuation of the foul alarm.

SUMMARY Basically the invention comprises a one-piece housing including a central chamber with a single light source therein, and a series of bores to permit light to radiate from said chamber in the direction of adjacent foul lines. Lens elements adjustably mounted upon the housing at the exit of the bores focus the light radiating therethrough upon retro-reflective discs mounted at the opposite ends of the foul lines. Semi-transparent mirrors disposed across said bores reflect light returning from the retro-reflectors to photoresistors mounted within the housing. A control circuit, including RC time constant elements in conjunction with programmed unijunction transistors as timers, and incorporating SCR and triac thyristers as power switching elements, responds to the photoresistor to actuate both visual and audio alarms for selected periods of time when the intensity of the light returning from the retroreflector falls below a selected value.

Among the advantages to be gained by practice of the invention are:

All active elements of a two lane foul detection system are combined in a single housing, so that a single electrical power lead is all that is required to provide power for the foul detectors for two adjacent bowling lanes;

The dual foul detecting unit of the invention may be placed within the narrow confines of a standard lane divider;

Need for installation, maintenance and alignment of light sources remote from the detection units is eliminated.

A more precise measurement of the time permitted for ball passage provided by the control circuit of the invention prevents spurious activation of the alarms.

The use of programmed unijunction transistors in conjunction with electronic flip-flop elements in the timer circuits permits more accurate measurement of the selected time periods and a more positive switching action at the end of such periods.

The use of SCR and triac components to control power to the alarms provides a maximum of power consistent with low control voltage.

Other objectives, advantages and various further features of novelty and invention will be pointed out or will occur to those skilled in the art from a reading of the following specification in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a detector of the invention installed in the divider strip between two adjacent bowling lanes.

FIG. 2 is a partially cut away side elevation of a foul detecting unit of the invention.

FIG. 3 is a partially cut away top view of the foul detecting unit of FIG. 2.

FIG. 4 is a partial schematic illustration of the invention including a partial cross sectional view of a detector housing of the invention taken along Line 4-4 of FIG. 2.

FIG. 5 is a schematic layout of an electrical alarm circuit of the invention.

FIG. ti is a plan view of a resilient mirror mounting gasket of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS As two like alarm systems comprise a goodly portion of the embodiment of the invention here disclosed, a description of one will suffice. Where applicable the letters "A" and 8" will be used to distinguish like elements associated with adjacent bowling lanes A and B.

Referring to FIG. 1, the active elements of a foul detection system of the invention are all contained within and beneath a metal cover 1. The cover I is coextensive with the lane divider l4 and extends onto an approach area 3 serving two adjacent bowling lanes A and B. Foul lines 4 and 5 mark the beginning of lanes A and B respectively and are not to be crossed by the bowlers foot during the delivery of his ball to the lane.

Each side of the cover 1 is provided with an opening 6 aligned with the axis of the foul line to provide an unobstructed light path therealong to a lens 7 positioned beneath the cover 1. In operation, light is projected through the lens 7 and focused upon a disc 8 of retroreflective material positioned at the other end of the foul line on the opposite side of the lane. This light is retro-reflected by the disc 8 back through the lens 7 and onto a photoresistor 21 of an alarm circuit as will be explained. The alarm circuit actuates an alarm when the light reflected to the photoresistor 21 is interrupted by a contestants foot. The alarm system provides a visual indication of a foul by lighting a lamp 15 which illuminates a window 10 on the side of the cover 1 facing the offending contestant, and sounds a buzzer 48 positioned beneath the cover 1.

The retro-reflective disc 8 may be easily mounted upon any ball return structure, such as the side of ball return track 11, as it is a thin wafer of material and easily attached to any flat surface. Retro-reflective material such as that described in U. S. Pat. No. 3,405,025 to W. A. Goldman may be employed for disc 8, however, other retro-reflective materials available on the open market are also suitable.

FIGS. 2 and 3 illustrate the orientation of the detection apparatus beneath and within the cover 1. The lenses 7A and 7B are adjustably attached to opposite sides of a solid machined housing 12. The housing 12 is mounted upon a chassis 9 which is fastened to the lane approach 3 with lenses 7A and 7B aligned upon the common axis of foul lines 4 and 5 respectively. An alarm circuit board 22 is mounted upon the chassis 9 behind the housing 12. The buzzer 48 and the power supply 60 for the system are mounted upon a downwardly extending portion 23 of the chassis 9, and are protected by a box-like cover 13 for which a recess 49 must be provided within the lane beneath the cover 1. The sockets 16 for foul indicating lamps are fastened by a clip 24 to the chassis 9 in position to illuminate the windows 10 in the near end of the cover 1. The photoresistor 21, lamps 15, power supply 60 and buzzer 48 are connected by electrical leads to the circuit board 22 at a junction box 23 adjacent the end of the circuit board.

Referring to FIG. 4, the housing 12 is an integral structure providing the various recesses, chambers and slots required to accommodate all of the optical and photoelectrical elements of the foul detection unit. A chief objective of this construction is to reduce the width of a dual detection unit to approximately 4 inches so that it will fit within a lane divider strip 14 recognized as minimum by the ABC. This requirement is of particular importance when the foul detection units are utilized with bowling lanes employing covered surface ball returns or modifications thereof (see FIG. 1), as there is no space available within such returns to accommodate foul detecting equipment.

The basic elements of a foul detection unit of the invention include a light source bulb 17, a partially silvered semi-transparent mirror 18, a lens 7, a retroreflective disc 8, a photoresistor 21 and the associated alarm circuitry.

Light from the bulb 17 passes outwardly through the semi-transparent mirror 18 and is focused by the lens 7 upon the retro-reflective disc 8 at the opposite end of the foul line. Light reflected by the disc 8 returns through the lens 7 and strikes the mirrored surface 19 of the semi-transparent mirror 18. The plane of the mirror 18 is perpendicular to the horizontal plane containing the foul line, and set at an angle of 45 with the axis thereof. Light returning from disc 8 is reflected horizontally at substantially a right angle to the foul line onto the sensitive face 20 of the photoresistor 21.

The lamp 17 is positioned within a central light chamber 28 formed by a centrally located horizontal bore communicating with the forward face 27 of the housing 12. Light passage through the housing 12 to the lenses 7A and 7B is provided by principal light passage bores 33A and 33B which extend laterally on either side of the central bore 28 to the side faces 25 and 26 respectively of the housing 12. The principal light passages 33 taper at the inner end and communicate with the light chamber 28 through orifices 30 having a diameter substantially smaller than that of the bores 33. The axis of lateral bores 33 and the orifices 30 align with the filament 50 of the lamp 17. The filament 50 falls at a focal point of the lenses 7 which are designed by known methods to focus the image of the filament 50 upon the retro-reflectors 8, and thereby concentrate the light at the point of reflection. The diameter of orifices 29 and 30 is such that all the light radiated therethrough will fall upon the inner surface of the lens 7. The walls of the bores 33 and 36 are painted with nonreflective black paint to discourage random reflection of the light which would reduce the sensitivity of the photoresistor and consequently the sensitivity of the alarm circuit.

Each lens 7 is mounted within a frame plate 37 which is adjustably attached to the housing 12 by screws 38 passing through elongated holes 39 in the plate 37. This mounting permits fine adjustment of the lens to its foul line. The lens plates 37 seal the exterior ends of the light passage bores 33 and 36 from dirt and dust generated so abundantly by the bowling game and lane maintenance.

The lamp 17 is removably retained by a conventional pin and slot arrangement within a receptacle 32 and is sealed within the chamber 28 by a cover plate 42 extending across the front face 27 of the housing 12.

The semi-transparent mirrors 18 are positioned within slots 35 cut into the housing 12 and extending across the light passage bores 33 at angles of 45 to the axes thereof. Slots 35 communicate with the top 43 of the housing 12, and angle inwardly from the sides 25 and 26 respectively of housing 12 toward the photoresistors. Each mirror 18 is retained within its slot 35 by the lens retaining plate 37, and by an opaque oval gasket 34 of resilient polyurethane foam (see FIG. 6) wedged between the mirror and a wall of the slot 35. Mirror 18 and gasket 34 are equal in peripheral dimensions, so that the gasket 34 serves to resiliently retain the mirror 18 within the slot 35, to protect it from vibration and shock, and to seal the slot 35 against the entry of dust.

The photoresistor 21 is positioned within the outer end of a secondary light passage bore 40 which communicates with the principal light passage bore 33 through an orifice 41, also of reduced diameter. The axes of bores 40 and 33 lie within a common plane and intersect at right angles, and at a point on or near the reflective surface 19 of the mirror 13.

The size of the housing 12 is determined principally by the diameter and focal length of the lens '7, the interrelationship of the size and length of the bores 33 and rib, and the orifices 30 and 41. As is best illustrated in FlG. 4i, the inner end of bore 33 tapers conically to an intersection with the central light chamber 23 forming an orifice 30 having a relatively sharp edge 31. As indicated by the lines 36, light radiating from the filament 5% will be restricted by the orifice 30 to a conical beam which fans outwardly to just match the circumference of the inside face 52 of the lens 7.

The bore 40 is reduced to an orifice 41 where it intersects the bore 33. The location of the bore Ail, its depth, and the diameter of the orifice 33 are such that any light reflected by the edge 31 of orifice 30 will not reach the sensitive face of the photoresistor 21L The most critical path of such reflected light is represented by the line 29 (FIG. 4) extending from the point on the edge 31 of orifice 30 furtherest away from the photoresistor 211 to the point at the edge of the orifice All near est the light source. Light reflected along this line will fall upon the wall of bore 40 at a point 42 and will be absorbed by a black non-reflective coating thereon. The photoresistor 21 is positioned within the bore All with its sensitive face outside the closest point of approach 42 of such reflected light; and is maintained in this position by a retaining bracket 55 removably attached to the housing 12. To maximize the sensitivity of the system the photoresistor 21 is positioned the same distance from the lens 7 as the filament 59, so that the image returning from the retro-reflector 8, and reflected by the mirror 18, will be focused on its photosensitive face. The size of the orifice 41, the diameter and depth of bore 40 and the positioning of the photoresistor 21 are therefore determined not only by the path of outgoing light but also to the path of returning light.

FIG. 5 is a schematic of an electrical circuit for a dual foul detecting unit of the invention described above. As the circuitry is basically the same for each lane, only one side of the circuit will be described.

Referring to FIG. 5, one side 61 of a photoresistor 211 is connected to a +5v DC power pick-off 59 from an AC power source 60, and the other side 62 to the junction of a resistor R2 and to an input 63A of a Schrnitt trigger circuit 63. It will be understood by those skilled in the art that as the amount of light returing from the retro-reflector 8 is reduced, the resistance of photoresistor 21 increases, resulting in the triggering of the Schmitt circuit 63 at a voltage regulated by the photoresistor 21 and a resistor R2 connected in series with the photoresistor 21 across the +5v DC power supply. Triggering of the Schmitt circuit 63 causes current to flow to the 80 ms timer circuit 65, through a resistor R8 and to start to charge a capacitor C2. At the end of approximately 80 ms, if the trigger circuit 63 has not been returned to the dormant state by the removal of the ob ject (such as a passing ball) blocking the light path, the capacitor C2 will be sufficiently charged that its potential will be momentarily applied to the emitter 6d of a programmed unijunction transistor or lPUT" Q3. The PUT" O3 is programmed by resistors RM) and Rlll to conduct when the charge on capacitor C2 and applied to its emitter 64, has reached a selected voltage. As the time required for the capacitor C2 to reach this voltage (approximately ms) is determined by the time constant of the combination of C2 and R8, their values control this initial time delay period within acceptable margins of 10 percent eliminating any need for tuning of variable elements as required by Brown. The 80 ms delay circuit 63 is built into the system to prevent the indicating of a foul when the bowling ball passes over the foul line.

The 80 ms delay circuit 65 connects to a twelve second timer and control circuit 66. When the lPUT Q3 becomes conductive at the end of the 80 ms period, the capacitor C2 discharges therethrough to the base 67 of a transistor Q il, causing it to conduct. Current flowing through the transistor Q4 effectively grounds one point 69 on the set side of a set-reset solid state flip-flop 70. As point 6% goes low, the output point 68 on the set side of the flip-flop 70 goes high. Point 63 is con nected to an input point 72 on the reset side of the flip-flop 70 and, through a resistor R19, to the gate 76 of an SCR thyrister Q7. As long as point 72 and the gate is of the SCR Q7 remain high the SCR will conduct a half-wave voltage. The SCR Q7 is in series with a foul lamp l5 and the AC power supply 60, so that the AC current will flow and illuminate the lamp 15 as long as the voltage at gate 76 of the SCR Q7 remains high.

Simultaneously with the activation of the twelve second timer es and the foul lamp 15, a buzzer 48 is actuated through a similar three second timer circuit 77. This buzzer timer circuit 77 also has a set-reset solid state flip-flop 30, one input 83 of which is connected to the input 69 of the twelve second timer flip-flop 70 through an inclusive or gate 85. In the event that another foul is committed on the paired lane within the three second time period, the or gate 85 will assure that only one three second buzzer signal sounds.

One input fill on the reset side of the buzzer flip-flop {i0 is connected to the base 86 of a transistor Q10. The collector d7 of the transistor Q10 is connected through a resistor R27 to the gate 88 of a triac Qlll. Triac Qlll is in series with the buzzer 48 and the AC power source us. When point 69 is driven low, point 811 and the voltage to the transistor base 86 goes high, transistor QM conducts and sufficient voltage is applied to the gate 83 of the triac Q11 to cause it to become conductive and energize the buzzer 48 with full wave power.

Like timer circuits are employed to turn off the foul lights and the buzzer. When the terminal 72 of the light timer flip-flop ill goes high and fires the SCR Q7, as described above, the timer portion of the circuit 66 is activated. This timer portion includes a resistor RM, a capacitor C3 and a PUT" Q5. The resistor RM is connected between the terminal 72 of the flip-flop 70 and the junction between the capacitor C3 and PUT Q5. When terminal 72 goes high C3 begins to charge through RM. When C3 becomes sufficiently charged, in about 12 seconds, a time period determined by the time constant ofRM and C3 and resistors RM and R17 which program the PUT" 05, the PUT Q5 conducts. Current then flows through the PUT Q3 to the base 7d of a transistor Q6 rendering it conductive. The transistor Q6 is connected between the terminal 73 on the "reset side of the flip-flop 70 and the low side of the power supply 60, so that when it conducts the terminal 73 goes low and the flip-flop 70 is reset. With the resetting of the flip-flop 70, point 72 also goes low and the positive bias to the gate 76 of the SCR Q7 is re moved. The SCR Q7 will then turn itself off at the next half cycle and will remain off until the input point 69 of the timer control circuit 66 is again driven low.

The buzzer 48 is turned off by the action of a similar timer portion of the control circuit 77, including a time constant circuit R22-C6, a PUT Q8 and a transistor 09. It takes about 3 seconds for the capacitor C6 to fill sufficiently to cause the transistor Q9 to conduct and drive the input terminal 89 of the buzzer flip-flop 80 low. This resets the flip-flop 80 causing the input terminal 81 to go low. When the input terminal 81 goes low, the positive bias to the gate 86 of the transistor Q10 is removed and it ceases to conduct, the positive bias to' the gate 88 of the triac Q11 is removed and it returns to the non-conductive state cutting off the power to the buzzer 48.

A similar combination of the circuits 63, 65 and 66 is provided for the foul light of the other lane of the pair, however, both foul light circuits connect to the single buzzer control circuit 77 as illustrated.

The invention employs a unique combination of solid state flip-flops and unijunction transistors to achieve a reliable timer and control circuit. The circuit as designed employs off-the-shelf components and achieves a stability making the use of variable value components and frequent tuning unnecessary.

We claim:

1. A bowling foul detecting and indicating device comprising:

means for projecting a light beam along a foul line of a bowling lane,

means for reflecting said light beam back to said projection means,

means for detecting an interruption of said reflected light beam, and

means responsive to said detecting means for signaling a foul when the interruption of said reflected light beam exceeds a preselected time period, including a foul signaling device,

a first timer means for determining if the interruption of said reflected light beam exceeds a preselected time period containing a first RC time constant circuit charged by the detection means having an output and a first programmed unjunction trsnsistor means for providding a first timer output signal when the first unijunction transistor conducts and means for programming said first unijunction transistors to conduct when the output voltage of said RC timer circuit attains a preselected voltage level, and means responsive to said first timer means output signal for actuating said foul signaling device, including second timer means responsive to said first timer means for deactivating said foul signaling means at the expiration of a second preselected time period, said second timer means including an electronic set-reset device having a set and a reset side, said set side being connected to the output of said first programmed unijunction transistor, a second RC time constant circuit connected to a first terminal on the reset side of said set-reset device, a transistor having an emitter connected to a second terminal on said rest side and a collector connected to ground, and a second programmed unijunction transistor and means for programming the same, said second programmed unijunction transistor having an emitter connected to the output of said second RC time constant circuit and a collector connected to the base of said transistor, whereby the second terminal on the reset side of said setreset device will be connected to ground when the output of said second RC time constant circuit attains a voltage level predetermined by said programming means for said second unijunction transistor.

2. The device of claim 1 wherein said means responsive to said first timer means for activating said foul signaling device comprises an SCR having an emitter and collector connected in series with an AC line power supply and said foul signaling device and a gate connected to the first terminal on the reset side of said setreset device, whereby half wave line power will be supplied to said foul signaling device when said SCR is biased to conduct. 7

3. The device of claim 1 wherein said means responsive to said first timer means for activating said foul signaling device comprises a second transistor and a triac, the emitter of said second transistor being connected to said DC power supply, the collector to the common gate of said triac and the base to the first terminal on the reset side of said set-reset device, so that full wave line power will be supplied to said foul signaling device whenever said second transistor and said triac are biased to conduct.

* i i I? 

1. A bowling foul detecting and indicating device comprising: means for projecting a light beam along a foul line of a bowling lane, means for reflecting said light beam back to said projection means, means for detecting an interruption of said reflected light beam, and means responsive to said detecting means for signaling a foul when the interruption of said reflected light beam exceeds a preselected time period, including a foul signaling device, a first timer means for determining if the interruption of said reflected light beam exceeds a preselected time period containing a first RC time constant circuiT charged by the detection means having an output and a first programmed unijunction transistor means for providing a first timer output signal when the first unijunction transistor conducts and means for programming said first unijunction transistor to conduct when the output voltage of said RC timer circuit attains a preselected voltage level, and means responsive to said first timer means output signal for actuating said foul signaling device, including a second timer means responsive to said first timer means for deactivating said foul signaling means at the expiration of a second preselected time period, said second timer means including an electronic set-reset device having a set and a reset side, said set side being connected to the output of said first programmed unijunction transistor, a second RC time constant circuit connected to a first terminal on the reset side of said set-reset device, a transistor having an emitter connected to a second terminal on said rest side and a collector connected to ground, and a second programmed unijunction transistor and means for programming the same, said second programmed unijunction transistor having an emitter connected to the output of said second RC time constant circuit and a collector connected to the base of said transistor, whereby the second terminal on the reset side of said set-reset device will be connected to ground when the output of said second RC time constant circuit attains a voltage level predetermined by said programming means for said second unijunction transistor.
 2. The device of claim 1 wherein said means responsive to said first timer means for activating said foul signaling device comprises an SCR having an emitter and collector connected in series with an AC line power supply and said foul signaling device and a gate connected to the first terminal on the reset side of said set-reset device, whereby half wave line power will be supplied to said foul signaling device when said SCR is biased to conduct.
 3. The device of claim 1 wherein said means responsive to said first timer means for activating said foul signaling device comprises a second transistor and a triac, the emitter of said second transistor being connected to said DC power supply, the collector to the common gate of said triac and the base to the first terminal on the reset side of said set-reset device, so that full wave line power will be supplied to said foul signaling device whenever said second transistor and said triac are biased to conduct. 